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A073478
Expansion of (1+x)^(1/(1-x)).
2
1, 1, 2, 9, 44, 290, 2154, 19026, 186752, 2070792, 25119720, 334960560, 4824346152, 75100568088, 1250180063664, 22235660291880, 419595248663040, 8388866239417920, 176823515257447104, 3923498370610292544
OFFSET
0,3
LINKS
FORMULA
E.g.f.: exp( Sum_{n>=1} x^n * Sum_{k=1..n} -(-1)^k/k ). - Paul D. Hanna, Jan 08 2014
a(n) ~ (log(2))^(1/4) * exp(2*sqrt(n*log(2)) - n - 1/2) * n^(n-1/4). - Vaclav Kotesovec, Apr 21 2014
MATHEMATICA
CoefficientList[Series[(1+x)^(1/(1-x)), {x, 0, 20}], x] * Range[0, 20]! (* Vaclav Kotesovec, Apr 21 2014 *)
PROG
(PARI) {a(n)=n!*polcoeff((1+x +x*O(x^n))^(1/(1-x)), n)} \\ Paul D. Hanna, Jan 08 2014
(PARI) {a(n)=local(A); A=exp(sum(m=1, n, sum(k=1, m, -(-1)^k/k)*x^m)+x*O(x^n)); n!*polcoeff(A, n)} \\ Paul D. Hanna, Jan 08 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladeta Jovovic, Aug 26 2002
EXTENSIONS
More terms from Robert G. Wilson v, Aug 28 2002
STATUS
approved